Local staging of rectal cancer: Diagnostic potential of endorectal contrast agent and MPRs with 64-MDCT compared with the pathologic staging

PurposeTo assess the diagnostic potential of endorectal contrast agent and multiplanar reconstructed images (MPRs) with MDCT in local staging of rectal cancer compared with the pathologic staging.Patients and methodsThis study included 30 patients with biopsy-proven rectal cancer (age range 18–84 years, mean 46.7 ± 19). Preoperative MDCT examinations were performed to all patients using a 64-row multidetector scanner. The examination was carried out in two steps, firstly using oral contrast agent only, secondly using endorectal contrast agent. Images were reconstructed in axial, coronal, and sagittal planes. MDCT staging was compared with pathologic staging.ResultsFor T-staging, MDCT using endorectal contrast was more sensitive (75.8%), specific (90%) and accurate (86.7%) than using oral contrast only (43.3%, 88.1%, 74.4%) respectively (p = 0.001). The sagittal and coronal MPRs were more sensitive, specific and accurate than the axial images with diagnostic accuracy 64.4% for axial, 75.5% for coronal, and 81.1% for sagittal MPRs. There were statistically significant differences between axial and coronal MPRs (p = 0.02), and between axial and sagittal MPRs (p = 0.002). Diagnostic accuracy for N-staging was 80%.Conclusion64-MDCT with endorectal contrast agent and MPRs, mainly sagittal images is a reliable accurate technique for the preoperative local staging of rectal cancer.